An open International Conference on the Sodium Pump is planned for September 5-9, 1990, at the Marine Biological Laboratory, Woods Hole, MA. It is the sixth in a series of triennial meetings, the third held in the U.S., and the first sponsored by the Society of General Physiologists. Its proceedings will be published by Rockefeller University Press, and distributed with the Journal of General Physiology. The pace of research on the sodium pump is accelerating, especially in the areas of molecular biology and structure-function relationships, charge translocation and voltage dependence, and presteady-state kinetics and ion occlusion. The conference will offer a timely opportunity for experts in these not (yet) overlapping fields to compare notes in an intensive five-day discussion, and to disseminate their conclusions to an audience much wider than the participants or the Society's membership, in particular, to colleagues working on other members of the E1-E2 transport ATPase family. Five major themes will be covered: (1) Molecular Biology of the Sodium Pump, isoforms, regulation, and designed mutants; (2) Structural Studies both empirical (two-dimensional crystals, chemical modification, and site mapping) and theoretical (from primary sequences); (3) Conformational Changes and Ion Occlusion, as measured from intrinsic and extrinsic signals and from isotope "trapping"; (4) Detailed steady-state and presteady-state ('fast') kinetics of the various modes and intermediate steps in the pump cycle; and (5) Electrogenicity and voltage dependence with emphasis on identifying the voltage sensitive (charge translocating) step(s) in the cycle. Furthermore, if new developments justify it, a Workshop may be hold on endogenous pump regulators. Twenty-seven, including thirteen non-U.S., speakers have been invited to present comprehensive critical reviews of their own work and that of others, and to write a chapter for the proceedings. The lecture program will be held during five morning sessions. The remaining time will be devoted to poster sessions related to the meeting's themes, with 24-h access. Prof. H.C. Khorana has agreed to deliver the keynote address. The proceedings, to be published within 10 months of the meeting, will consist of chapters corresponding to the chairmen's introductions and invited lectures, and of short-paper versions of the relevant posters.